Generator, converter, and alternate-current motor.



v. A., FYNiN.

v GENERATOR, CONVERTER, AND ALTERNATE OURRBNT MOTOR.

APPLICATION FILED MAY 8, 1907.

Ins-8,49% Patented July 29, 1913.

' X REGULATING RESISTANCE I mug/W01; valz e A. Fynn 98 7 O Y L L- J V.A. PYN N. GENERATOR, CONVERTER! AND ALTERNATE CURRENT MOTOR.

APPLICATION FILED MAY 8, 1907.

,Patented July 29, 1913 REGULATINQ RESISTANCE K REGULATING RESDSTANCEREGULATINGVRESI'STANCE' WE/wok- Valere A. Fynn WITNESSES.

I Y IVEYS 4 v v. A. FYNN. GENERATOR, CONVERTER, AND ALTERNATE CURRENTMOTOR. APPLICATION FILED MAYB, 1907.

1,068,494. Patented July 29, 1913."

3 SHEETS-SHEET 3.

WIT/M8858" INVENTOH if; Valgre kzFynn' UNITED strarnirginnr OFFICE.

VALERE ALFRED FYNN, OF BLACKHEATI-I, ENGLAND.

GENERATOR, CONVERTER, AND ALTERNATE-CURRENT Moron.

specification of Letters Patent.

Patented July 29, 1913.

Application filed May 8, 1907. Serial No. 372,516.

To all ie/tom 4t may concern:

Be it known that 1, Vatican Armani) FY N, of 1S Blessinp'ton road,Blackheath, in the county of Lent, England, electrical engineer, haveinvented. certain new and use ful Improvements in Generators,(,onverters, and rillternate-Current Motors, of which the following is aspecification. 4 I

lily invention relates to a machine capable of bein operated as analternate current motor or generator and particularly suitable foroperation as'a single phase rotary converter.

The objects oi? my invention are to provide a motor which will startwith a powerful torque and will run with a high power factor whenoperated from a single phase supply, or a machine which while operatedas a converter. 1'. as a combined motor and generator may be startedwith ease and with very little current from the alternating side andwill be free from hunting and spar-lo ing. I achieve these objects bycombining in one and the same machine the hereinafter defined featuresor constructive elements of an asynchronous and of a synchronousalternate current machine. When my machine is operating as a motor theasynchronous or synchronous features only or the combina-- tion of theasynchronous and the synchronous features are made use of in order tostart the motor with ease while in normal operation the syi'ichronousfeatures are made use of to improve the power factor, the nonsvnchronousfeatures being made use of to obviate all possibility of hunting andalso to increase the overload capacity for their presence makes itpossible for the machine to also work asynchronously. \Vhen such amachine is operating as a generator the ncirsynchronous features greatlysimplify the paralleling and the parallel running while the synchronousfeatures provide the seli' Xcitation. l-Vhen such a machine is(){J'Ql'tii'ilig as a converter, that IS, a combined motor andgenerator, the asynchronous or synchronous features only, or acombination of the asynchronous with the synchronous features are madeuse of to start the machine with ease, while in normal operation theasynchronous features are made use of to avoid all 'iossibility ofhunting and also to increase the overload capacity, the synchronousfeatures being made use of either I to improve and to regulate the powerfactor or to regulate the voltage of the continuous current or generatorside or for both purposes. The more detailed descriptions of myinvention will all refer to two pole machines when nothing to thecontrary is stated, but

it will be understood that this invention is applicable to machines withany number of poles.

My invention will perhaps be more easily understood by reference to theaccompanying drawings, in which,

Figure 1 shows the general disposition of circuits of a machineconstructed according to this invention and capable of' operating as asingle phase motor, generator or converter. Fig. 2 shows a form of rotorwinding particularly well suited for use in a single phase motor. Fig. 3shows the arrangement of circuits and switches for start ing a singlephase motor as a shunt conduction machine and operating it as aselfexcited synchronous mot-or also capable of running as an asynchronousmachine or as a converter. l ig. shows a modification of Fig. 3 in whichpart. of the polyphase stator winding is combined with that windingwhich in normal operation provides theexciting field. Fig. 5 shows thearrangement of circuits and switches for starting a single phase motoras a. self-excited series induction motor and operating it as indicatedin connection with F ig. 3. Fig. (5 shows the arrangement of circuitsand switches for starting a single phase motor as a separately cX- citedseries induction motor and operating it as indicated in connection withFig. '3. Fig. 7 shows the arrangement d f clrcuits and switches forstarting a single phasemotor partly as a separately and partly asself-excited series induction motor and operat ng it as indicated inconnection with Fig.

3. Fig. 8 shows a'modifica-tion of Fig. 5.

practice consist broadly in suitably combining with a rotor connected tothe alternate current supply by means of slip rings, a field structureof the stator type, that is one without defined polar projections,further in providing means for suitably exciting the machine from therotor, and also provlding means which will enable the machine to operateas a. non-synchronous alternate current. motor.

In applying my invention to a single phase alternating current motoralso capable of operating as a converter, I provide the rotor as shownin Fig; l of the drawings with an ordinary continuous current winding Wconnected on one side to a commutator in the usual way, while twosuitably chosen points of the same winding are connected to two sliprings R It, on the other side. I also provide a laminated fieldstructure of the stator type and two sets of windings thereon preferablyembedded in slots' provided in the stator. T he one winding F isarranged to be connected to the brushes B, B bearing on the commutator,the other S, S, is preferably of a polyphase type and arranged to beeither connected to the supply or short-circuited on itself.

The asynchronous and synchronous features or constructive elements whichare combined in these improved machines and which are referred to in thedescription as well as in the claims may be defined as follows:

The asynchronous features or construe tive elements consist of-- l. Astationary member in the form of what is known as a stator or alaminated ma netic structure without defined polar projections.

9. A revolving member in the form of what is known as a rotor on alaminated magnetic structure without defined polar projections.

. 3. One mcn'iber'carrying windings adapted to receivealternatecurrents, either single or polyphasc. through a suitable number of sliprings or otherwise.

4, The other member carrying polyphase windings adapted to beshort-circuited. This member may, for instance, carry a three-phasewindini that is, one con'iprising three windings displaced by 240/ndegrees.,which may be interconnected or not or, it may carry a two-phasewinding interconnccted or not, but displaced by 180/n degrrees, and soon. The letter n stands throughout for the number of poles of themachine.

The syimhronous features or. constructive elements consist ot,-

A winding" disposed on at least one member and adapted to produce, atleast at synchronous spccdsf' a unidirectional magnctization (in respectof that member on which it is disposed) by means of contin'u ous currentsent through it and usually de rived from the machine itself.

6. A commutator connected to the whole or to part of the windingsdisposed on one member in conjunction with brushes bearing on saidcommutator which brushes may be connected to the windings specifiedunder (5), to an external load or to both.

For the sake of convenience these various features will in future bereferred to by the numbers under which they are specified. They are ofcourse subject to slight modifications as will hereinafter be pointedout.

Where rotor windings of the continuous current type are made use of theywill be represented by a circle which may stand for the usual Grammering type of winding and where brushes are used it will be supposed thatthese bear directly on this Grannne ring winding although in practice acommutator will of course be used.

I will now describe with the help of Fig. 3 how a single phase motorconstructed according to this invention may be started as a shuntconduction motor (neutralized or not).

The mains indicated by A A are connected by way of switches L to thestator winding 8., disposed coaxially with F. The brushes B, and B areconnected to the winding F. ll he stator winding S, which is displacedby 180/n degrees (where 1] stands for the number of poles of themachine) from S is short-circuited or not as may be desiiged; if it isshort-circuited the rotor ampere turns along the axis of the brushes arepartly neutralized.

The alternating E. M. F. applied to S sets up an alternating field alongthe axis of F and induces therein a secondary E. M. h. which isimpressed on the rotor by way of the brushes 13, lg. If the rotor ampereturns are not neutralized the rotor will have a large self-induction andthe current.- due to the secondary l). M. F. will lag considerablybehind the latter and will therefore approach the phase of the fieldproducing that secondary E. M. F. A torque will result between the fielddue to S which represents the motor field and the rotor current. Thistorque will however diminish rapidly with increasing speed principallybecause currentand motor field will tend to get more andv more out ofphase.

The current on switching in can be regulated by means of lever K or theregulating resistance X or by varying the l). M. F. impressed on 5%,, orin any of the well known ways. \Vhen K is on point. 1 no F. F. at all isimpressed on the rotor. The current. taken by the motor and the torquewill increase tln' K is moved toward point 4 or as X is reduced. 'lhedirection of rotation can be reversed by reversing the current throughthe rotor by means of Z. When the motor has nearly reached its full orsynchronous speed, the supply is disconnected from S. thrown on to theslip rings by way of the switches L which are moved on to points 7, 8and S and S. are shortcircuited by means of K and K As soon as SVIX(lU'()I1OHS speed is reached the current flowing from the rotor intoF becomes continuous and can be adjusted by means of. K or X or by bothso as to produce that unidirectional magnetization which yields eitherthe best mean power factor orthe best power Factor for a given load.lVhen desired an adjustment can be made for every or any load but thatof course is not. necessary tor the successful operation of the motor.When desired the motor can be made to take leading currents.

It the motor gets overloaded it can slip out of synohronism when it cancontinue to work as an asynchronous motor with the.

help of the short-circuited polyphase winding S S disposed on thestator. That same winding will also check any tendency of the motor tohunt when running synchronously.

will be not or that the rotor as shown in Fig. must be wound for thefull line' pres sure for that figure indicates a simple Gramme ringwinning W connected to two slip rings it. and R and to a commutator onwhich rest the brushes B and The pressure of the supply is often highand it the rotor winding just described were used on high voltagecircuits, a high voltage would also result at the brushes B and B thiswould lead to sparking and would necessitate a great number of turns inthe winding F. One 'ay in which this ditliculty can be obviated is tomake use on the rotor of a combined continuous currentand alternatecurrent winding, the former being closed on itself wnilc the latter atone end connected to the forn'ier and at the other to slip rings -asshown diagrammatically in Fig. 2 for the case of a single phase rotor.Winding. in this manner the voltage at the (,Oll'lll'lll? tator willonly depend on W whereas the voltage at the slip rings will depend on W,A rotor wound as shown in F1; "ll "t'- l Y I 'tl tl '1'- 11 or tn Ht 3 oaway W1 1 n. spar mg ditliculty in normal operation and also reduce itto quite harmless proportions. at starting or even entirely obviate it.

Again referring to Fig. 2 the purely alternate current part (it therotor winding, that shown at W and "W can be otany well known type usedon alternate current ma.-

chines or it can also be a. continuous current winding suitablyinterconnected with \V on one side and the slip rings on the other. in afurther modification illustrated in Fig. 9 the winding \V, W", need haveno electrical.connection whatever with the winding l'V connected to thecommu. or.

In Fig. i is shown a modification in the disposition of the windingsplaced on the stator. The windings F andS are here combined into onewinding which at start ing is connected to the supply A A at 9 and 7.\Vhereas in Fig. 3 the primary S and the secondary F of the transformerin the axis of these two windings were separate they have been combinediuFi 4 after the style of an autotransformcr by means of which thetension to be applied to the armature may be as easily varied with thehelp of switch K as in the case of Fig. 3. \Vhen in normal operation theswitch K short-circuits that portion of the combined winding F-S whichis not made use of for excitation purposes.

In Fig. 5 is shown a single phase motor constructed according to thisinvention and adapted to be started as a self-excited series induct-ionmotor. The rotor carries a combined winding such as is also shown inFig. 2; the stator windings are disposed similarly to those of Fig. 3but in this case. it is the winding S coaxial with the commutator brushline, which isproportioned for diroot or indirect connection to themains whereas S may have any convenient number of turns. The winding Fis connected in series with the continuous current winding WV on therotor by means of the brushes B B The transformer field due to Sproduces at B B an F. M. F. which forces a current through l'V and F.The current in these two windings is necessarily cophasal, the fieldproduced by F is cophasal with the current through F therefore with thecurrent through WV. The field produced by F is the motor field andproduces the torque with the current in iv. The maximum available torquewith a given terminal voltage depends on the number of turns in S Thenumber of these turns can be regulated in order to secure gradualstarting. The torque and the current taken by the motor for a givennumber of turns in S. can be regulated by means of K, to' one andcurrent being a minimum when K stands on point 1, for the reason thatall the turns of F are then in circuit with the brushes B B Theimpedance.v ot' the armature circuit is thus very large and the'eurrentinduced therein by S, is consequel'itly small. A resistance at X or anyother well known regulating means may be employed.

At starting in the manner shown in Fig.

5 the winding S is on open circuit and the slip rings are not connectedto the mains. \Vhen a sufficient speed has been reached the supply isdisconnected from S and connect;

ed to points 7 and 5 by way of the switches L, the windings S S areshort-circuited by means of the switches K K and the winding F adjustedfor instance with the help of K and X to give the desired power factor.

In this case as in all others the various changes indicaeo tan becarried out gradually or suddenly as desired. The c lireetion ofrotation ".an be reversed by reversing the current through I 2'. 6., byreversing the motor field by means of Z.

A further means for starting a single phase motor according to thisinvention is shown in Fig. 6. As the connections are shown the motorwill start as a separately excited series induction motor The wind ing Sand part of the combined winding F and S are connected in series acrossthe 5 mains, the rotor is short-circulted 1n the axis of S by means ofthe brushes B B and the switch Y through point 5. The armature currentis therefore induced .in the short-circuitcd rotor by the transformerfield due to S and the motor field is excited by the winding FS or thatpart of it which the particular position of K includes in the circuitfor the time being. When the motor has reached a sullicient speed themains are disconnected from S and .ld-S and connected to points 6 and LGby way of the switches L at the same time S and S are short-circuited byK and K and the rotor brushes connected to a suitable amount of winding1* through a regulating resistance X by throwing; the switch Y on; topoint- 6. The direction of rotation can be altered by revin'sing'thecurrent through F by means of Z.

In Fig. 7 is shown a motor constructed ac cording to this invention andarranged to st art partly as a separately and partly as a self-excitedseries induction motor The polyphase winding disposed on the stator andforming the asynchronous teaturc -lis ol the lhrce phase type. The threephases are at starting all connected in scrics across thc mains and insuch a way that two of them, say H and S produce an alternating licld inth axis l; B vhereas the third prodnccs an alternating fieldperpendicular to 1& 13 At the. same time the brushes l3, l3 arcconncctcd to i for in stance as in Fig. in whc as thc'slip ring circuitis lcl'l opcn. It is seen that in this lorn'i of the in\'cntion thewhole of the cop per on lhc slator is a lirc throughout.

'lhc transformer field due to B and induces a currcnt in W which alsoflows through i thus part of the motor l'icld is cxciled by the armalnrccurrcnt flowing; through I this is the Hllt-lXi'iltll field. The statorcurrcnl llowing through ti excites another part ol the motor licld.'ihcsc two windings may be made o cooperate or to oppose *ach other,thus. varyin g the starting torque, which can. vol conrsc, be varied bymeans of K, and X or by any well known means. When the motor has reacheda autii cicnt speed the mains are (llHflUIiF-(Hil'til trom S S S andswitchcd on to the slip rings at points 8 and 10 by way of the switchesL at the same time all stator windings with the exceptionot F areshort-circuited by K K K when the excitation producing theunidirectional field at synchronism can be suitably adjusted as hasalready been fully explained. The direction of rotation can be reversedby means of the switches Z and Z.

The motor constructed according to this invention and shown in Fig. 8also starts as a self-excited series induction motor in the same manneras has for instance been more fully described in connection with Fig. 5.In this figure, however, the arrangement of the stator windings issomewhat diiierent. The winding F is the same as in previous figures butthe stator winding which is short-circuited in normal operation is byway of example carried out exactly like a threephase star winding ofvery few turns of thick wire per phase. The relative position of any onephase to any of the other stator windings is immaterial. Coaxially withthe brushes B B is disposed the starting windiiig S which need only bewound with fine wire and this at starting is conneeted to the mains.\Vhen the motor has reached a sufliciently high speed the three phasewinding S S 3;; is short-circuited by K and K after the mains have beendisconnected from S and connected to the slip rings at the points 8 and10 by way of the switches L. The winding 8, may or may not beshort-circuited as well. The excitation at F is adjusted as in theprevious examples.

In Fig. 9 is shown one scheme of connections for a motor starting andoperating smnewhat like the motor shown in Fig. 7. The dili'crence isthat only a two-phase winding 8. S is supposed to be used on the statorpositioned as shown for instance in Fig. 5. and the rotor is supposed tocarry two distinct windings. The contact arm N is shown in the oltposition 0. When inovcdto position .i only the stator windillQ'S are incircuit and it is not until the motor has gathered speed that the sliprings are connected to the supply. As N moves farther the tcnsion acrossthe slip rings increases and that across S and S diminishes until thelatter are totally short-circuited. The torque and current can at thesame time be regulated with the help of K or X or both. When h, and Sare short-circuited the starting transformer '1 can be disco-nncctcdfrom the supply for instance by opening switch iii.

in Fig. 10 is shown a motor constructed according to this invention andstarted as a series conduction motor. The part S of the multiphasewinding on the stator always remains short-circuitcd, the winding therotor by way of the brushes B B and any part of F are connected inseries across the mains. After the motor has reached asufiicient speedthe mains are disconnected from the windings named 5 above andconnectedto the slip rings by moving the switches L from points 7 and 9to points 8 and 10 and the switches K and K are closed. SwitchKshort-circuits S and K connects the brushes to the winding F which canbe now adjusted as previously explained,

Fig. 11 illustrates that construction of the stationary part I and therevolving part D of these machines which is essential for theirsatisfactory operation. This construction tion for the revolving'fluxesset up'in these machines. The stationary part I has a number of slots IIin which are located the windings S, S and F of Fig. while the windingsll, W are located in the slots G of the revolving part D.

The hereinhei'ore described machines can be employed as self-excitinggenerators if mcclninically driven: they will operate very readily inparallel with other generators and it will not be necessary tosynchronize them accurately before switching them on to the supply, theunidirectional exciting circuit being closed only after such a generatorhas been connected to the mains. If brought up to approximately theirsynchronous speed without unidirectionalexcitation, and connected inparallel with other generators, they will take such a wattlessalternating current from the other generators as will enable the severalshort-circuited stator windings to produce the necessary excitation inthese machines to enable them to operate as asynchronous generators whendriven at sutliciently high speed. By closing the unidirectionalexciting circuit, these machines may be converted into synchronousgenerators, in which case the several short-circuited stator windingswill serve to damp out the double frequency armature reaction component.

These same machines will also operate as converters and are particularlywell adapted for converting single phase into'continuous current andvice versa. Single phase converters have always been very diilicult tostart from the alternate current side requiring a quite abnormal currentfor this purpose. My improved machine entirely obviates this difficultyfor the various methods of starting which have been described inconnection with the drawings are all very effective and will enable themachine to be brought up to speed as an alternate current motor with afraction of its full load cur rent. Single phase converters asordinarily constructed are liable to hunt and to spark at the commutatorand the design of 55 my improved m i h e as herein described secures apractically constant iron cross sec-,

also does away with those ditliculties because of the use of a field.structure of uniform cross section all around and because ofthepolyphase winding on'this structure. In making use of these machines forconverting alternate into continuous current they can, for instance, bestarted like an alternatmg current motor in any one of the waysdescribed in this specification, and when running synchronouslyalternate current being supplied to the slip-rings, continuous currentcan be taken from the brushes on the commutator by means of suitableleads and conveyed to any desired translating devices. When convertingfrom continuous to alternating current the machine, ofcourse, operatessimultaneously as a continuous current motor and as an alternatingcurrent generator, the alternating current being taken from slip-rings.The essential elements comprised in my improved dynamo electric machineand enumerated in this description are made use of in all cases andwhether the machine operates as an alternate current motor or generatoror as a converter.

\Vhat I claim and desire to secure ters Patent is:- p I v 1. In adynan'io electric machine, the combination with a source of single-phasecurrent, of a stator provided with an exciting winding and with at leasttwo other windings disposed along axes displaced by less than 360/11degrees, a rotor having a winding connected to slip-rings, a commutatorand means for connecting it to theexciting winding, means forshort-circuiting the other two stator windings, and means for connectingthe source of single-phase current to one of the stator windings forstarting and to the slip-rings for running.

2. In a single-phase converter, the combination with a source ofsingle-phase current, of a stator provided with an exciting winding andwith another winding displaced therefrom, means for establishing aplurality of short-circuits on the stator along'dift'erent axes, arotorhaving 'a'winding connected to slip-rings, a commutator and brushesthereon, mans -tor connecting the brushes to the exciting winding, thecircuits of the machine being so arranged at starting as to cause analternating current to be established throughthe rotnr by Way of thebrushes along an axis dis 'ilaced vfrom one of the stator windings, andmeans for connecting the source oi singlc phasecurrent to the slip ringsfor running.

In a dynamo electric machine, the com bination with a sour e ofsingle-plan current, of a stator provided with an exciting winding andat least two other windings displaced by less than 360/11 degrees, arotor having a commuted winding, means for connecting the commutedwinding to the exciting winding, slip-rings connected to the byLetcommuted winding, means for connecting the source of single-phasecurrent to one of the stator windings for short-circuiting two of thestator windings.

4. .ln a single-phase converter, the combination with a source ofsingle-phase current, of a. stator having no defined polar proectionsand provided with an exciting wind- I ing and another winding displacedtherefrom, means for establishing a plurality oi. short-circuits on thestator along different I axes, a rotor having a winding connected toslip-rings, a commutator and brushes thereon, and means for connectingthe brushes to the exciting winding, the circuits or the ma- I chinebeing so arranged at starting as to cause an alternating current tobeestablished through the brushes and also through a stator windingdisplaced from the brush axis, and means for connecting the source ofsingle-phase current to the slip-rings for running.

5. In a dynamo electric machine, the combination with a source ofsingle-phase current, of a stator provided with at least two windingsdisposed along axes displaced from each other by less than 360/11degrees, a rotor having a. winding connected to sliprings, a commutator,an exciting winding along the axis of one or the other stator windings,means for connecting the source of single-phase current to at least oneof the stator windings for-starting and to the slip-rings for running,and means for shortcircuiti'ng two of the stator windings.

6. In a dynamo electric machine, the com bination with a source ofsingle-phase current, of a stator provided with an exciting winding anda second winding disposed along an axis displaced by less than 360/ndegrees from the exciting winding, a rotor t having a winding connectedto slip rings, a' commutator with brushes thereon,.means for connectingthe brushes to the exciting winding, means for connecting the source ofsingle-phase current o one of the stator windings for starting and tothe slip-rings for running, and means for establishing a plurality ofshort-circuits on the stator along different axes.

7. In a dynamo electric machine, the combination with a source ofalternating current, of a stator provided with an exciting t startingand to degr'ees,

the slip-rings for running, and means for winding,

on the stator connected to said commutator winding and at least twoother windings displaced from each other by less than 360/n means forsliortcircuiting said two last named windings, a rotor having slip ringsand a commuted winding, means for connecting the commute-d winding tothe exciting winding, an additional winding on the rotor connected to aslip-ring, and means for connecting the source of alternating current toone of the stator windings for starting and to a slip-ring for running.

8. In a dynamo electric machine, stator provided with an excitingwinding and two windings displaced from each other, means forshortcircuiting said two last named windings, a rotor having slip-rings,a commuted winding, and an additional winding connected to the commutedwinding and to a slip-rin 9. In. a dynamo electric machine thecombination with a stationary member without defined polar projectionsand provided With an. exciting winding and at least two other windingsdisposed along axes (lisplaced trom each other by less thaaBi'iO/ndegrees, of a revolving member without defined polar projections havingacommuted means for connecting the commutcd winding to the excitin wind Islip rings, and an additional winding connected to the commuted windingand to a i and means for sl'iort-circuiting two of stator winding.

10. In a single-pl'n'isc converter, the coinbination with a source ofcurrent, of a stationary member without defined po ar pro jections andprovided with two windings displaced from each other by less than Sou/ndegrees, means for shorucircuiting said windings, a revolving member.without defined polar projections having a commutator and a windingconnected to citing winding on the stationary member til L:

connected to the commutator, and means for connecting the source ofcurrent to a winding on the stationary member for the. giurpose ofstarting the converter.

In witness whereof, I hav hereunto signed my name in the presence of twosubscribing witnesses. I

NALERE ALFRED FYNN.

lVitn esses:

ROBERT MILTON H. D. JAMnsoiv.

SPEARPOINT,

slip-rings, an eX-

